Many formulations such as inks, paints, mill bases, and plastics materials require effective dispersants for uniformly distributing a particulate solid in an organic medium. The organic medium may vary from a polar to non-polar organic medium. Dispersants containing terminal basic groups such as poly(lower alkylene)imine chains are well known and are generally prepared by reaction of the polyamine with polyester chains containing terminal acid groups, the reaction results in a mixture of amide and salt forms. However, many of these dispersants have limited performance towards viscosity and stability properties, which when incorporated into printing inks or paints, give the inks and paints with poor flow characteristics. Therefore, there is a need for a dispersant capable of providing acceptable performance towards at least one of flow characteristics, viscosity and stability properties.
U.S. Pat. No. 5,721,358 which discloses a process for copper phthalocyanine production using a dispersant derived from a non-salted succinimide dispersant. The succinimide dispersant is derived from an alkyleneamine and polyisobutylene succinic anhydride.
U.S. Patent Application 2003/0213410 discloses a polymer-modified pigment comprising a polymer with at least one carboxylic group or salt thereof and at least one coupling agent. The polymer includes derivatives of polyamines that have been reacted with an acylating agent such as acetic or succinic anhydride.
GB 1,373,660 discloses polyesteramine dispersants obtainable by reaction of polyhydroxycarboxylic acids with diamines especially alkylenediamines and their salts thereof.
U.S. Pat. No. 5,000,792 discloses polyesteramine dispersants obtainable by reacting 2 parts of polyhydroxycarboxylic acids with 1 part of dialkylenetriamine.
Therefore, it would be advantageous to have a dispersant with acceptable viscosity and stability properties, which when incorporated into printing inks or paints, give the inks and paints with acceptable flow characteristics.